Circuit for balancing potential fluctuations



April 5,1949. L. BLQK 2,466,299

CIRCUIT FOR BALANCING POTENTIAL FLUCTUATIONS Filed March 25, 1943 vzInrG i 3 4 6-o 1 4 5 a 1 T E iNVENTOR LOURENS BLOK ATTORNEY Patented Apr.5, 1949 CIRCUIT FOR BALANCING POTENTIAL FLUCTUATIONS Lourens Blok,Eindhoven, Netherlands, assignor to Hartford National Bank and TrustCompany, Hartford, Conn, as trustee Application March 23, 1943, SerialNo. 480,185

In the Netherlands September 17, 1940 Section 1, Public Law 690, August8. 19%

Patent expires September 17, 1960 3 Claims.

.similar fluctuations and this is in some cases inadmissible, forexample in the-case or" a lowfrequency oscillator to be used formeasuring or adjusting purposes.

For stabilizing supply voltages it is known to use glow discharge lampswhich are operated in the substantially flat part of the current-voltagecharacteristic curve. Thus, however, complete compensation is notobtained. and moreover it is necessary for a sufiiciently largeregulating range to choose the current that passes through the lamp soas to be at least as high as the supply current, the efficiency beingthereby interfered with.

The present invention meets the said two dii ficulties.

According to the invention, one of the terminals of the source of directvoltage between pensation or over-compensation of the potentialfluctuations which is desired for any case is reached.

v If therefore the output of a direct voltage as constant as possibleis, for example, required a 100% compensation will have to be providedfor.

If, however, the point in question is the directcurrent supply of anaggregate comprising a plurality of discharge tubes it is preferable toover-compensate and to supply only part of the said tubes, if possibleonly one, with the (over)- compensated voltage and all the other tubeswith the non-compensated voltage. In the case of sufficientover-compensation the same effect is thus nevertheless achieved asthough all of the tubes were supplied with a perfectly constant voltage,and there is by now the additional advantage that the current and hencethe loss of energy in the regulating impedance may remain small.

In this manner it is possible, for example with a low frequencyoscillator, to provide for an out put which is independent of potentialfluctua tions of the electric lighting mains, in that only one of thetwo oscillators, whose difference irequency constitutes the desired lowfrequency, is supplied with the overcompensated direct voltage, but theother oscillator and the amplifier with the non-compensated voltage.

In order that the invention may be clearly understood and readilycarried into efiect this embodiment of the invention will now be described-more fully with reference to the accord panying drawing, inwhich one example is grammatically shown.

Between the terminals l and 2 of a source direct voltage, for example ananode tension supply unit, there is a voltage E which may vary inconsequence of supply voltage fluctuations and/or temperaturefluctuations.

A low frequency oscillator T is supplied from. the terminals E and 2with the interposition of a resistance R2 and is provided for thispurpose with connecting terminals and i. The oscillator part G is,however, precluded from this supply and separate connecting terminals 5and ii are provided for its supply.

In view of the latter terminals, the terminal (i is connected to theright hand end of the resist ance R2, whereas the terminal 5 isconnected to the point of connections between a resistance R1 and a glowdischarge lamp L which are connected in series between the terminals land 2.

In these circumstances potential fluctuations between i and 2 willbecome manifest in com paratively unweakened condition between 3 and 4so that if the output T has to remain unaltered the voltage between 5and 6 will have to manifest similar but oppositely directed potentialfluctuations. This result may be obtained by means of the illustratedcircuit arrangement by a suitable amazes choice of the resistances R1and Re, as will be set out in greater detail.

The resistance R1 is naturally to be chosen so that at the mean value ofE the lamp L operates about centrally in its regulating range so thatthe value of the said resistance is thus fixed.

If designating the instantaneous voltage across the glow discharge lampby V0, that between the terminals 5 and 6 by V and the current in theresistance R: by i we have the ratio:

V=V0-R2i and in the case of low variations of E:

AV+AVo=R2Ai Emean V01tS 300 R1 -9" 1600 R2 ..Q 1000 imean 8.-- 55Potential variations of E up to about can be balanced completely bymeans of this circuit arrangement.

Instead of using the glow discharge lamp L, use may of course be made ofother impedances provided that their differential resistance is lowerthan R2 or than the diflerential resistance of the circuit element whichwould take the place of R2.

I claim:

1. In combination with a source of direct current voltage subject tofluctuation and an electrical system provided with two pairs ofenergizing terminals, a first resistor and solely a. single glow lampconnected in series across said voltage source, a second resistor havinga resistive value substantially less than the magnitude of the firstresistor, said second resistor being connected in a series circuit withsaid first resistor and glow lamp between one pair of said energizingterminals, and said lamp and second resistor being connected in aseparate series circuit between the second pair of energizing terminals.

2. In combination with a source of direct-current potential subject tofluctuation and an elec-- trical system provided with two pairs ofenergizing terminals, a circuit for balancing potential ing one of saidtwo pairs of terminals in series with said second resistor to said glowlamp, and means connecting the other of said two pairs of terminals inseries with said second resistor to said source of direct-currentpotential.

3. In combination with a source of direct-current potential subject tofluctuation and an electrical system provided with two pairs ofenergizing terminals, a circuit for balancing potential fluctuations atsaid terminals comprising a first resistor, a singlepotential-regulating glow lamp having a predetermined operating rangeconnected in series with said first resistor to said source ofpotential, the resistance of said first resistor having a value at whichat the mean potential value of said source of potential said glow lampoperates in a central portion of said predetermined range, a secondresistor, means connecting one of said two pairs of terminals in serieswith said second resistor to said glow lamp, and means connecting theother of said two pairs of terminals in series with said second resistorto said source of direct-current potential, the resistance of saidsecond resistor having a value at which the potential fluctuationsappearing at said one pair of terminals are of equal magnitude butoppositely directed with respect to the potential fluctuations appearingat said other pair of terminals.

LOURENS BLOK.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS FOREIGN PATENTS Country Date Great Britain 1943Number Number

